Vasculopathies, cutaneous necrosis and emergency in dermatology.

Most emergencies in dermatology comprise a variety of entities with a usually benign course. However, vasculopathies and vasculitis are not common, but they could represent respectively 1.9% and 4.4% of these entities according to some studies of Emergency Dermatology Department. They become an important disease which has to be identified early to establish appropriate management and treatment. Some of them are well known, such as the leukocitoclastic vasculitis, Schölein-Henoch, panarteritis nodosa, antineutrophil cytoplasmic antibody associated vasculitis, giant cell arteritis, cryoglobulinemic vasculitis and antiphospholipid syndrome. More frequent vasculopathies are livedoid vasculopathy, pigmented purpuric dermatosis and calciphylaxis. Less common ones are caused by interferon and cholesterol crystal embolization. Others are very infrequent as Degos disease and Sneddon Syndrome. Among the more recently described ones there are deficiency of adenosine deaminase type 2 and crystalglobulinemia. The other group is composed of vasculopathies associated to microorganism as infective endocarditis, septic vasculopathy, aspergillosis, fusariosis, strongiloidosis, ecthyma gangrenosum, lucio phenomenon of leprosy and necrotic arachnidism. Finally, among these entities we can also find diseases associated with proinflammatory stages as disseminated intravascular coagulation, myeloproliferative disorders, intravascular lymphoma, metastasis intravascular. When we face cutaneous lesions characterized by reticulated violaceous lesions, palpable purpura or cutaneous necrosis, a careful clinico-pathological correlation as well as some laboratory or radiological tests are mandatory to further delineate a diagnosis and a proper first line empirical treatment.

Occlusive Nonvasculitic Vasculopathy.

We review the most characteristic clinical and histopathologic findings of the cutaneous manifestations of the occlusive nonvasculitic vasculopathic disorders. Clinically, most of these conditions are characterized by retiform purpura. Histopathologic findings consist of occlusion of the vessel lumina with no vasculitis. Different disorders may produce nonvasculitic occlusive vasculopathy in cutaneous blood and lymphatic vessels, including embolization due to cholesterol and oxalate emboli, cutaneous intravascular metastasis from visceral malignancies, atrial myxomas, intravascular angiosarcoma, intralymphatic histiocytosis, intravascular lymphomas, endocarditis, crystal globulin vasculopathy, hypereosinophilic syndrome, and foreign material. Other times, the occlusive disorder is due to platelet pugging, including heparin necrosis, thrombocytosis secondary to myeloproliferative disorders, paroxysmal nocturnal hemoglobinuria, and thrombotic thrombocytopenic purpura. Occlusive vasculopathy may also appear in cold-related gelling agglutination, like that occurring in cryofibrinogenemia, cryoglobulinemia, cold agglutinin syndrome, and crystalglobulinemia. Microorganisms may also occlude the vessels lumina and this is especially frequent in ecthyma gangrenosum, opportunistic fungi as aspergillosis or fusariosis, Lucio phenomenon of lepromatous leprosy and disseminated strongyloidiasis. Systemic coagulopathies due to defects of C and S proteins, coumarin/warfarin-induced skin necrosis, disseminated intravascular coagulation, and antiphospholipid antibody/lupus anticoagulant syndrome may also result in occlusive nonvasculitic vasculopathy. Finally, vascular coagulopathies such as Sneddon syndrome, livedoid vasculopathy, and atrophic papulosis may also cause occlusion of the vessels of the dermis and/or subcutis. Histopathologic study of occlusive vasculopathic lesions is the first step to achieve an accurate diagnosis, and they should be correlated with clinical history, physical examination, and laboratory findings to reach a final diagnosis.